In this respect, the requirements for the joining connection are many and varied. For example, temperature-sensitive polymers, organic substances and/or materials with different thermal expansion coefficients, and components with temperature-sensitive materials must be connected to one another. In many applications, especially, in industrial process measurement technology, it is required that joining connections be hermetically sealed. This is significant in that adhesive connections are largely ruled out. Welded connections and soldered connections are indeed hermetically sealed, but are problematic, in that their production thermally stresses the joining partners, especially if the surfaces to be joined between the joining partners are to be brought to the melting temperature of the soldering material by heating the joining partners.
For this reason, reactive material systems are basically attractive for connecting temperature-sensitive joining partners, in particular. Reactive material systems allow even propagating exothermic reactions that are already used in other areas of application for joining components. In this respect, there are basically two variants. On the one hand, thermal reactions in powder mixtures are used to fuse substances; on the other hand, even propagating reactions are used in nanoscale multilayer systems in the form of foils, in order to fuse solder layers and thus create a joining connection. The reactive material systems with nanoscale multilayer systems in the form of foils are offered, for example, by the Indium Corp. under the designation, NanoFoil®. For microsystems technology applications, it is, however, difficult to activate the joining process in a controlled manner and to let it take place in a sufficiently precisely localized manner with defined energy density. In addition, such foils are difficult to manufacture and, therefore, suitable only with restrictions, especially for applications in microsystems technology.